Hello!:
Molar mass:
HBr = 80.91 g/mol
HNO3 = 63.01 g/mol
Number of moles:
moles HBr = 1.0 / 80.91 => 0.01235 moles of HBr
moles HNO3 = 1.0 / 63.01 => 0.01587 moles of HNO3
So , total moles of H⁺ :
0.01235 + 0.01587 => 0.02822 moles of H⁺
Molarity of solution:
M = n / V
M = 0.02822 / 5.0
M = 0.005644
Therefore:
pH = - log [ H⁺ ]
pH = - log [ 0.005644 ]
pH = 2.25
Hope that helps!
